﻿using Wrox.ProCSharp.Common;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices.WindowsRuntime;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Navigation;
using Wrox.ProCSharp.Repositories;
using Wrox.ProCSharp.Model;
using System.Collections.ObjectModel;
using Wrox.ProCSharp.Storage;
using Windows.UI.Popups;

// The Items Page item template is documented at http://go.microsoft.com/fwlink/?LinkId=234233

namespace Wrox.ProCSharp
{
  /// <summary>
  /// A page that displays a collection of item previews.  In the Split Application this page
  /// is used to display and select one of the available groups.
  /// </summary>
  public sealed partial class MainPage : Page
  {
    private NavigationHelper navigationHelper;
    private ObservableDictionary defaultViewModel = new ObservableDictionary();

    /// <summary>
    /// This can be changed to a strongly typed view model.
    /// </summary>
    public ObservableDictionary DefaultViewModel
    {
      get { return this.defaultViewModel; }
    }

    /// <summary>
    /// NavigationHelper is used on each page to aid in navigation and 
    /// process lifetime management
    /// </summary>
    public NavigationHelper NavigationHelper
    {
      get { return this.navigationHelper; }
    }

    public MainPage()
    {
      this.InitializeComponent();
      this.navigationHelper = new NavigationHelper(this);
      this.navigationHelper.LoadState += navigationHelper_LoadState;
    }

    /// <summary>
    /// Populates the page with content passed during navigation.  Any saved state is also
    /// provided when recreating a page from a prior session.
    /// </summary>
    /// <param name="sender">
    /// The source of the event; typically <see cref="NavigationHelper"/>
    /// </param>
    /// <param name="e">Event data that provides both the navigation parameter passed to
    /// <see cref="Frame.Navigate(Type, Object)"/> when this page was initially requested and
    /// a dictionary of state preserved by this page during an earlier
    /// session.  The state will be null the first time a page is visited.</param>
    private async void navigationHelper_LoadState(object sender, LoadStateEventArgs e)
    {
      this.DefaultViewModel["Commands"] = this;

      var storage = new MenuCardStorage();
      MenuCardRepository.Instance.InitMenuCards(new ObservableCollection<MenuCard>(
          await storage.ReadMenuCardsAsync()));
      this.DefaultViewModel["Items"] = MenuCardRepository.Instance.Cards;

    }

    #region NavigationHelper registration

    /// The methods provided in this section are simply used to allow
    /// NavigationHelper to respond to the page's navigation methods.
    /// 
    /// Page specific logic should be placed in event handlers for the  
    /// <see cref="GridCS.Common.NavigationHelper.LoadState"/>
    /// and <see cref="GridCS.Common.NavigationHelper.SaveState"/>.
    /// The navigation parameter is available in the LoadState method 
    /// in addition to page state preserved during an earlier session.

    protected override void OnNavigatedTo(NavigationEventArgs e)
    {
      navigationHelper.OnNavigatedTo(e);
    }

    protected override void OnNavigatedFrom(NavigationEventArgs e)
    {
      navigationHelper.OnNavigatedFrom(e);
    }

    #endregion

    private RelayCommand addCommand;
    public RelayCommand AddCommand
    {
      get
      {
        return addCommand ?? (addCommand = new RelayCommand(OnAdd));
      }
    }

    private void OnAdd()
    {
      Frame.Navigate(typeof(AddMenuCardPage));
    }

    private RelayCommand deleteCommand;
    public RelayCommand DeleteCommand
    {
      get
      {
        return deleteCommand ?? (deleteCommand = new RelayCommand(OnDelete));
      }
    }

    private async void OnDelete()
    {
      var selectedMenuCard = itemGridView.SelectedItem as MenuCard;
      if (selectedMenuCard != null)
      {

        var dlg = new MessageDialog(string.Format("Delete the menu card {0}?", selectedMenuCard.Title));
        dlg.Commands.Add(new UICommand("Delete", new UICommandInvokedHandler(DeleteMenuCard)));
        dlg.Commands.Add(new UICommand("Cancel"));
        await dlg.ShowAsync();
      }
    }

    private void DeleteMenuCard(IUICommand command)
    {
      var menuCards = this.DefaultViewModel["Items"] as ObservableCollection<MenuCard>;
      if (menuCards != null)
      {
        menuCards.Remove(itemGridView.SelectedItem as MenuCard);
        // TODO: remove it from storage
      }
    }

    private void OnMenuCardClick(object sender, ItemClickEventArgs e)
    {
      Frame.Navigate(typeof(MenuItemsPage), e.ClickedItem);
    }
  }
}
